.TH std::experimental::ranges::ForwardIterator 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::experimental::ranges::ForwardIterator \- std::experimental::ranges::ForwardIterator

.SH Synopsis
   Defined in header <experimental/ranges/iterator>
   template< class I >

   concept bool ForwardIterator =
       InputIterator<I> &&
       DerivedFrom<ranges::iterator_category_t<I>,                          (ranges TS)
   ranges::forward_iterator_tag> &&
       Incrementable<I> &&

       Sentinel<I, I>;

   The concept ForwardIterator<I> refines InputIterator by adding equality comparison
   and the multi-pass guarantee.

   The domain of == for forward iterators is that of iterators over the same underlying
   sequence, except that value-initialized iterators of the same type may be compared
   with each other and shall compare equal.

   Pointers and references obtained from a forward iterator into a range [i, s) must
   remain valid while [i, s) continues to denote a range.

   Let a and b be two dereferenceable iterators of type I. ForwardIterator<I> is
   satisfied only if:

     * a == b implies ++a == ++b; and
     * The expression ([](X x){ ++x; }(a), *a) is equivalent to *a, i.e., incrementing
       a copy of a has no effect on the result of dereferencing a.

   This is known as the multi-pass guarantee.

.SH Notes

   A forward iterator cannot be "stashing": it cannot return a reference to an object
   within itself, because such references would be invalidated by the destruction of
   the forward iterator.
